The use of amplification techniques in a procedure for detection of a target molecules that include target nucleic acid sequences is well known in the art. Typically, this procedure includes enzymatic amplification of target nucleic acid sequences and detection of the target molecules by gel electrophoresis followed by Southern blot procedures.
A number of solid phase capture assays have also been developed to simplify the procedures for detection of target molecules including nucleic acid sequences. In these procedures two ligands are typically incorporated within amplified target nucleic acid sequences. A first ligand is used to capture, on a solid matrix, the target molecules that include the amplified target nucleic acid sequences and a second ligand is used to detect the target molecules by the binding of a signal producing reagent to this second ligand.
Solid phase affinity capture assays, however, require an extended reaction time to capture a high proportion of target molecules in a reaction mixture (Sauvaigo et al., Nucleic Acid Research, 1990, Vol. 18, pp. 3175-3182). Furthermore, when capture is mediated by amplification primers incorporating a solid phase affinity ligand, the sensitivity of the assay may be adversely effected by competition between free primers and primers incorporated in the target nucleic acid sequences.
The use of chromatography as a separation and concentration procedure is well known in the art. It has been reported that whereas DNA molecules are chromatographically mobile on moistened paper they fail to migrate when solutions are applied to dry paper (Bendich et al., Arch. Biochem. Biophys., 1961, 94, 417-423).